Compositions effective for controlling dust mites and the allergens produced by dust mites

ABSTRACT

Alcohol based aerosol spray compositions which contain 1-20% of an alcohol-soluble polymer which, on evaporation, leaves on a sprayed surface a film which acts as a barrier to dust, dust mites and their faecal excretions. These compositions optionally can include an acaricidal ingredient, such as benzyl benzoate, and one or more antimicrobial ingredients such as a quaternary ammonium salt.

FIELD OF THE INVENTION

This invention relates to alcohol-based disinfectant compositionscontaining one or more additional ingredients which form a barrieragainst dust particles and particularly dust mites and their allergens.More specifically, the invention relates to aerosol spray disinfectantssuitable for indoor use which, in addition to having the usualantimicrobial properties, are also effective in preventing people fromcoming in contact with allergens found in dust, notably dust miteallergens. The invention also provides methods for effectivelycontrolling dust mites and their allergens and for significantlyreducing their attendant adverse reactions.

BACKGROUND OF THE INVENTION

Common house dust is an important cause of asthma, rhinitis, atopicdermatitis, eczema and other allergic conditions in sensitiveindividuals. Household dust generally comprises a variety of particulatematter including pollen, dust mites, dust mite allergens, dirt, skincells, animal dander, insect parts, pillow feathers, food particles andmould spores. The particular constituents of dust will depend onlocation within the house, whether pets are present and other obviousfactors. One of the principal sources of allergies is dust mites, whichinhabit rugs, carpets, and other fabric surfaces, particularly sofas,mattresses, pillows, upholstered chairs and the like. The miteDermatophygoides pteronyssinus has been identified as a major source ofhouse dust allergen. This mite and the related mites D. farinae, D.microceras and Euroglyphus maynei are the predominant house dust mitesin temperate climates in North America, Europe, Australia and otherareas.

Dust mites are not insects, but are eight-legged arachnids, relatives toticks and spiders. They live in close association with humans (or othermammals), their main food source being the shed scales from skin. Adultmites are approximately 300 microns (3/10 mm) in size, having developedover approximately 25 days through egg, larval and nymph stages. Adultslive for 2 to 31/2 months, during which time each female can produceabout 20-40 eggs. Dust mites are photophobic, living deep in pillows,mattresses, carpets, upholstered furniture and other soft materials.

In addition to a food source, the other essential requirement for dustmite growth is adequate humidity. Dust mites are 75% water by weight.They do not drink water, but must absorb water vapor from the air inorder to survive. Specialized glands above their pairs of legs producesecretions high in sodium and potassium chloride, which act to absorbwater vapor from surrounding air. This can only be accomplished if thesurrounding humidity is sufficiently high. Relative humidities of about65-80% at temperatures ranging from about 20 to 35 C are optimal fordust mite growth. Dust mites will die at humidities of 50% or less. Ingeographical areas where humidity is high, dust mites are present innearly all homes and may be as plentiful as 18,000 mites per gram ofdust. Literally millions of mites can inhibit a single bed or rug.

A major dust mite allergen is present in mite faecal particles. Eachmite produces about 20 faecal particles per day, and more than 100,000of them may be present in a gram of dust. These particles vary fromabout 10 to 40 microns in size, comparable to the size of pollen grains,and become airborne during domestic activity such as making beds andvacuuming carpets.

Group I allergens (dermatophagoides farinae I-Der f I anddermatophagoides pteronyssinus I-Der p I) are heat labile, 24,000molecular weight glycoproteins (hydrolytic enzymes). These allergensappear to be structural homologues and have very similar N-terminalamino acid sequences. These group I allergens are regarded as the mostimportant and are excreted in their highest concentrations by the mite'sgastrointestinal tract in the form of mite's faecal particles,suggesting that they are associated with digestion. They elute rapidly(within 2 minutes) from isolated faecal particles, but very slow frommite bodies.

Group II allergens (Der p II and Der f II) are 15,000 molecular weightproteins with almost identical N-terminal amino acid sequences that arealso secreted by the mite's gastrointestinal tract in the form of faecalallergens, although not in as high a concentration as the group Iallergens. This suggests that they probably derived from a source otherthan the gut. Their actual function has not been determined.

Most mite-allergic individuals produce antibodies to both the group Iand group II allergens.

    ______________________________________                                        Allergen       Mol. Weight                                                                             pH                                                   ______________________________________                                        Group I                                                                       Der p I        24,000    4.6-7.4                                              Der f I        24,000    4.6-7.4                                              Group II                                                                      Der p II       15,000    5.0-6.4                                              Der f II       15,000    7.8-8.3                                              ______________________________________                                    

Acute exposure to mite allergens has been shown to induce wheezing,rhinitis, eustachian tube obstruction or eczema in sensitized patients.Chronic exposure can cause bronchial hyper-reactivity and chronicasthma. There is a correlation between the level of exposure to housedust mite allergen in early childhood and the likelihood of thesubsequent development of asthma. Conversely, asthmatics sensitive todust mites improve in environments without mites, such as at highaltitudes or in hospital rooms. Attempts have therefore been made todecrease patients' exposure to dust mites in the home.

Studies of dust avoidance measures in homes have shown that the use ofimpermeable mattress and pillow encasings and the removal of bedroomcarpeting are associated with a decrease in mite counts. These measureshave also been shown to be of clinical value, with a decrease insymptoms and medication requirements occurring in children and adultswith dust-sensitive asthma when pillows and mattresses are encased andcarpets are removed.

Although carpets and upholstered furniture are major sites of dust mitegrowth, many allergic individuals are unable or unwilling to removethese from their home. Ordinary vacuuming does not remove dust mites orsignificantly decrease dust mite allergen levels, and in fact, vacuumingof carpets with the usual household appliances actually increases theamount of airborne dust. However, the use of special filters such asHEPA (High Efficiency Particulate Air) filters or two-ply vacuum bags,and/or the employment of central vacuuming systems (where the dust iscollected in a receptacle remote from the room being cleaned) have beenhelpful. Nevertheless, vacuuming seldom removes all of the live mites,mainly because the mites have little suction cups on the tops of theirlegs which cause them to cling to textile fibres.

Various chemical agents have been used against mites, including:compounds known under the common names as resuethrin, phenothrin,permethrin, allethrins, tetramethrin, furamethrin, cypermethrin,decamethrin, phenvalerate, phenpropathrin, terallethrin, empenthrin andpyrethrin; pyrethroid compounds such as1-ethynyl-2-methyl-2-pentenyl-2,2-dimethyl-3,3-(2,2-dichlorovinyl)-cyclopropane-1-carboxylate,1-ethynyl-2-methyl-2-pentenyl-2,2,3,3-tetramethylcyclopropane-1-carboxylate,α-cyano-3-phenoxybenzyl-2,2-dimethyl-3-(2,2,3-tribromomethyl)-cyclopropane-1-carboxylate;organic phosphorus compounds such as sumithion, fenthion,tetrachlorvinphos, diazinon and DDVP; and carbamate compounds such asthose sold under the trademarks Baygon and Sevin. However, theseconventional miticides are expensive and are often either toxic to humanbeings or have the potential themselves to cause allergic or otheradverse reactions. Therefore, the use of such compounds in a householdenvironment cannot be the solution to controlling the population of dustmites.

A number of less toxic miticidal agents have been proposed for use incontrolling dust mites. As noted in U.S. Pat. No. 4,800,196, theseinclude phenyl salicylate, diphenylamine, methyl beta-naphthyl ketone,coumarin, phenethyl benzoate, benzyl salicylate, phenyl benzoate,N-fluorodichloromethylthio-cyclohexene-dicarboxyimide, p-nitrobenzoicacid methyl ester, p-chlorometaxylenol, α-bromocinnamic aldehyde,2,5-dichloro-4-bromophenol, 2-phenylphenol, sodium 2-phenylphenolate,5-chloro-2-methyl-4-isothiazoline-3-one, 2-methyl-4-isothiazoline-3-oneand benzimidazolylmethylcarbamate. These can be used in the form ofsolutions, wettable powders, granules, sprays, etc.

While many of these compounds have some degree of effectiveness againstdust mites, their use is not without attendant shortcomings. Forexample, many of them are rather expensive to produce and/or may bedifficult to form into compositions for ordinary domestic use.Elimination of dust in a household environment is a task which isintensely disliked to the point where the average householder is nolonger embarrassed by a moderate layer of dust or the presence of "dustbunnies" under beds or behind furniture. Furthermore, as noted above,dust removal and/or vacuuming often stirs up the dust mites and theirattendant allergens and, temporarily at least, causes more distress toallergic persons.

More effective methods of reducing exposure to dust mites and theirfaecal matter, have been developed which do not depend on the diligenceof the householder in removing dust.

U.S. Pat. No. 5,271,947 features the use of finely divided sodiumchloride powder as a method for killing mites and controlling theirallergen-bearing faeces. The powder has the consistency of talcum powderand is used, for example, by applying the powder with a broom or brushto carpets and other textile materials. However, one of thedisadvantages in using sodium chloride powder is its hygroscopicity; ifthe amount used is not carefully controlled, the salt will absorbmoisture from the air, particularly in humid climates.

One of the more effective agents for killing dust mites is benzylbenzoate, a compound which is readily available and inexpensive. Powderformulations containing benzyl benzoate are commercially available forapplication to carpets. British Patent No. 1,368,657 teaches the use ofa composition for treating bedding and similar materials which comprisesbenzyl benzoate and polyethylene glycol, or an ether or ester thereof,as an evaporation retarding agent. British Patent No. 2,042,893 teachesthe use of a composition comprising benzyl benzoate and a fatty acidester for application to bedding and also for treating the skin. Asimilar composition for general miticidal use in households is taught inpublished Japanese Patent Application No. 61-91103.

More generally, Bischoff U.S. Pat. No. 4,666,940 teaches the use ofvarious miticidal agents, including particularly benzyl benzoate, as acomponent in cleansing compositions. The disclosed compositions can alsocontain dissolved or dispersed plastic materials, but said materialsmust form discrete particles of particular size and must not form afilm.

European Patent Application No. 0,612,469 discloses laundry detergentscomprising benzyl benzoate, which compositions are taught to beeffective in killing the dust mites present on the articles to belaundered.

In an article by G. Schober et al., "Control of House-Dust Mites(Pyroglyphidae) with Home Disinfectants", Experimental & AppliedAcarology 3:179-89 (1987), the authors provide data showing that theaddition of benzyl benzoate to certain commercially available carpetcleaning formulations results in a composition with better acaricidalproperties than other known acaricides.

U.S. Pat. No. 5,180,586 discloses that certain compounds, previouslyknown for use as perfuming agents in foods and cosmetics, have beenfound to be effective in killing dust mites.

To summarize the published literature, it is apparent that benzylbenzoate and other miticidal compounds disclosed in the art can, underproper conditions of use, be effective in killing dust mites and thushelpful in reducing the level of allergens produced by said mites.Laundering and dry cleaning of textiles and fabrics can also beeffective under certain conditions, but this is not practical forday-to-day control.

The principal problem associated with previous methods for controllingdust mites and their allergens is the fact that frequently the mites andtheir faecal particles are not completely removed. At best, compositionscontaining acaricidally effective compounds will kill off the mites, butwill not remove their faecal matter and the associated allergens.Vacuuming, either by itself or as a final step in a method involvingchemical treatment, is often not effective because the pick-up nozzle ofthe vacuum cleaner cannot effectively fit into all of the crevices inupholstered furniture. Furthermore, unless vacuuming is done underspecial conditions such as use of a two-ply vacuum bag or HEPA filter,the allergens will be dispersed into the ambient air, therefore doingmore harm than good. Therefore, it would be desirable to have a methodfor controlling dust mites and their associated allergens which wouldavoid the various disadvantages of the methods heretofore used.

Accordingly, it is a principal object of this invention to provideimproved methods for controlling dust particles, in particular, dustmites and the allergens present in their faecal excretions.

It is a further object of this invention to prevent the allergenspresent in dust and, in particular, dust mites, from entering into theambient air of indoor spaces.

Another object of this invention is to provide compositions which can beused in attaining the aforementioned objects.

SUMMARY OF THE INVENTION

This invention provides alcohol-based aerosol spray compositions whichadditionally contain from about 1.0% to about 20.0% of a polymer whichis soluble in said alcohol and which, on evaporation, leaves on asprayed surface a film which acts as a barrier to dust, dust mites andtheir faecal excretions. (All percentages throughout this disclosure areto be understood as percentages by weight.) The compositions typicallyalso contain water in an amount ranging from 0 to 59%. Alternatively,the polymer can be one which is water-soluble, or one which is solublein both water and the alcohol; it is preferred that the polymer besoluble in at least the alcohol. In addition, the compositionsoptionally can include from about 0.1% to about 10% of an acaricidalingredient such as benzyl benzoate. Said compositions, in addition totheir usual disinfecting properties, are effective aids for controllingdust mites and, when the compositions also contain an acaricidalingredient, also kill the mites. The compositions can also comprise oneor more additional disinfectants such as a quaternary ammonium compound,a phenol-based antimicrobial agent, or a botanical oil with disinfectantproperties. The compositions can also comprise a suitable propellant,and other ingredients such as wetting agents, surfactants, preservativesand anti-corrosion agents.

The mites and allergens associated with dust mites can be controlled byapplying, more particularly by spraying, the compositions of thisinvention onto the surface of textile fabrics infested with said mites.This sets up a barrier which prevents the dust mites and their excretedfaecal matter from coming in contact with people. In addition, in theembodiment of this invention where the composition additionally includesan acaricidal ingredient such as benzyl benzoate, the mites are killedand the production of additional allergens thereby halted.

The method according to this invention comprises, in its broadest sense,spraying onto a textile fabric surface an alcohol-based disinfectingcomposition which contains from about 1.0% to about 20.0% of a polymersoluble in said alcohol and which, on evaporation, leaves on the surfacea film which acts as a barrier to dust mites and their faecal excretionsand to other particles present in household dust and their associatedallergens. The compositions typically also comprise water and,alternatively, the polymer can be one which is water-soluble. Thecompositions optionally can include from about 0.1% to about 10% of anacaricidal ingredient such as benzyl benzoate, in which case the methodis additionally a method for killing dust mites. In many circumstances,particularly with the infestation of dust mites is not great, thisspraying step will provide effective control of dust mite allergens bypreventing their escape into the ambient air.

A more effective method for control of dust particles, in particulardust mites and their associated faecal matter, is to remove as many dustmites and faecal particles as possible by vacuuming under conditionswhere the particles are not blown into the ambient air; for example,using a two-ply filter system or an HEPA system. The vacuuming step isthen followed up by spraying the fabric surface with a compositiondescribed above.

A still further procedure for dust mite control involves a three-stepmethod, the first step being application to the fabric surface, forexample, by spraying of a composition comprising a known acaricidalagent, such as benzyl benzoate. This is followed up, after a suitabletime for drying, by vacuuming as discussed above. In this procedure, thevacuuming step is somewhat more effective since most of the mites aredead and not clinging to the fibres. The final step is spraying thefabric surface with an aerosol composition according to this invention.

DETAILED DISCLOSURE

The aerosol compositions of this invention comprise, as essentialingredients, an alcohol having from 1 to 4 carbon atoms, preferablyethanol, and a polymer soluble in the alcohol, which results in abarrier film on a surface when the alcohol evaporates. The compositionswill typically and preferably also comprise up to about 15% of waterand, as an alternative, the polymer can be one which is soluble inwater. However, the use of an alcohol-soluble polymer is preferable inview of the faster evaporation rate of alcohol.

The compositions can also include an acaridical ingredient such asbenzyl benzoate or another known chemical substance effective againstdust mites such as those disclosed in U.S. Pat. No. 4,800,196, pertinentportions of which are incorporated herein by reference.

In view of the fact that dust mites are invisible to the naked eye, itis logical, from a commercial point of view, to control dust mitessimultaneously with killing or controlling other invisible organismssuch as bacteria. Aerosol disinfectant compositions have attained wideconsumer acceptance and the addition of one or more ingredients whichwill control dust mites and/or remove the dust mite allergens fromambient air has an extremely beneficial purpose and there is no need topersuade potential consumers to purchase an additional household careproduct specifically for the purpose of dust mite control.

As contemplated by this invention, the principal disinfecting ingredientis a low molecular weight alcohol, typically an alcohol having from 1-4carbon atoms such as methanol, ethanol or isopropanol, with ethanolbeing preferred. The disinfecting properties of such alcohols are wellknown. They form the basis of many commercial disinfecting compositionsand such compositions have attained great consumer acceptance. Inaddition to its disinfecting properties, the alcohol also functions as asolvent for the polymer and for some of the other ingredients optionallypresent in the compositions of this invention and provides for rapiddrying time in a household environment.

The amount of alcohol present in the composition ranges from about 30%to 90%, preferably from 70% to 85%, based on the weight of thecomposition, and exclusive of any propellent contained in saidcomposition.

Water, if present in the composition, can comprise up to about 59% ofsaid composition. Preferably, any water present will be in the 5 to 15%range.

The polymer used in the compositions of this invention is preferably onewhich is soluble in the alcohol component and must be a polymer which,after spraying and evaporation of the solvents in the composition, willleave a protective barrier film on the sprayed surface. Obviously, anysuch polymer must meet the criteria of consumer safety and, since thecontemplated use of the compositions is in an indoor environment, thepolymer should not have an offensive odor. All polymers which meet theforegoing criteria are suitable for inclusion in the subjectcompositions and these include, but are not limited to, polyesterresins, acrylate polymers and copolymers, methacrylate polymers andcopolymers, polyvinyl pyrrolidone and copolymers comprising vinylpyrrolidone, butyl maleate/isobornyl acrylate copolymers, thermoplasticpolyamides, nylon resins, polyvinyl alcohols and polyether polyols. Asuitable group of ethanol-soluble polymers are polyacrylates and theircopolymers. Because of their known safety, film-forming polymers used inhair treatment formulations have been found to be especially suitable.Examples include certain of the products sold under the following tradedesignations: Advantage CP, Gaffix, Gantrez and the PVP/VA Series ofInternational Specialty Products; Amphomer, Versatyl and Resyn ofNational Starch & Chemical Company; Dantoin of Lonza Inc.; Delsette ofHercules Incorporated; Diaformer of Clariant Corporation; Luviflex,Luviset, Luviquat and Luviscol of BASF Corporation; and Stepanhold ofStepan Company. These polymeric substances are generally soluble inethanol; some are also soluble in water. The significant feature of thepolymer useable in this invention is that it must form a film which willact as a barrier to both dust mites themselves and to their faecalexcretions. A powder is not suitable for this purpose, and likewise apolymer film which immediately breaks down to flakes or particles willnot be suitable. The film should remain intact for at least seven days,preferably for a period of from 10 to 30 days.

The amount of polymeric material in the composition is from about 1% toabout 20% by weight, preferably from 1% to 7%, and more preferably from2% to 5% by weight, exclusive of any propellent in said composition.

In another embodiment of this invention, the subject compositionsadditionally contain a miticidal ingredient, such as benzyl benzoate, inan amount of up to about 10% by weight. Preferably, the benzyl benzoateis present in an amount ranging from 0.5% to 8%, and more preferablyfrom 1% to 7%.

The compositions of this invention may also contain one or moreadditional antimicrobial agents in order to increase the antimicrobialeffectiveness of the composition up to a level defined by the UnitedStates Environmental Protection Agency as "hospital strengthdisinfection". The term "hospital strength" is not intended to indicatethat the subject compositions are restricted to use in hospitals andother health care facilities; rather such disinfectant compositions arecommonly sold for domestic use, and the term simply indicates a higherlevel of disinfective activity.

Although any known disinfecting agent can be used as an optionaladditional component, preferably the disinfectant agent will compriseone or more quaternary ammonium compounds commonly used as disinfectantsor one or more of the well known phenolic compounds such asortho-phenylphenol. The additional antimicrobial ingredient may bepresent in the composition in amounts ranging from about 0.01 weightpercent to about 1 weight percent, preferably from 0.05 to 0.5 weightpercent, and more preferably about 0.1%, based on total weight of thecomposition.

If the additional antimicrobial component is a quaternary ammonium salt,any of the broad classes of suitable quaternary ammonium compounds maybe used. More than one quaternary ammonium compound is employed toassist in providing a broader spectrum antimicrobial efficacy. Usefulquaternary ammonium compounds include, for example, those quaternaryammonium compounds represented by the formula: ##STR1## wherein R₁, R₂,R₃, and R₄ may be described in three general groups. The counterion Xmay be any salt-forming anion which permits water solubility of thequaternary ammonium complex. Exemplary counterions include halides, forexample chloride, bromide or iodide, or methosulfate.

In a first group of preferred quaternary ammonium compounds, R₁ and R₂are C₁ -C₇ alkyl groups (preferably methyl groups); R₃ is a benzyl groupor a benzyl group substituted with an alkyl group having about 1 to 18carbon atoms or an alkyl group having about 8 to 20, and preferably 8 to18, carbon atoms; R₄ is a benzyl group or a benzyl group substitutedwith an alkyl group having about 1 to 18 carbon atoms, and R₄ is abenzyl group or a benzyl group substituted with an alkyl group havingabout 1 to 18 carbon atoms or an alkyl group having about 8 to 20, andpreferably 8 to 18 carbon atoms.

In a second group of preferred quaternary compounds, R₁, R₂ and R₃ areC₁ to C₇ alkyl (preferably methyl groups); and R₄ is an alkyl, analkyl-substituted benzyl, or a phenyl-substituted alkyl group having atotal of from about 8 to 20, and preferably 8 to 18, carbon atoms.

In a third group of preferred quaternary ammonium compounds, R₁ is analkyl, an alkyl substituted benzyl, or a phenyl substituted alkyl grouphaving a total of from about 10 to 20, and preferably from 12 to 16carbon atoms; R₂ is a C₁ -C₇ alkyl (preferably a methyl group); R₃ is[CH₂ CH₂ O]_(x) H; and R₄ [CH₂ CH₂ O]_(y) H, with the sum of x+y varyingbetween about 2 and 50 (preferably 2 and 5). For all these groups, X maybe a halide (preferably chloride or bromide) or may be a suitableorganic anion such as benzoate or saccharinate.

Quaternary ammonium compounds are well known and available commerciallyfrom a number of suppliers. For example, dialkyl dimethyl ammoniumchloride is available in approximately 50% active ingredient solution asBardac-2050 quaternary ammonium compound from Lonza, Inc. (Fairlawn,N.J.) and Bio-Dac-50-20 quaternary ammonium compounds is available fromBio-Labs (Decatur, Ga.), both of which are mixtures of approximately 25%octadecyl dimethyl ammonium chloride, about 10% dioctyl dimethylammonium chloride, about 15% didecyl dimethyl ammonium chloride in asolvent solution containing about 10-20% ethyl alcohol and 30-40% water.Also, for example, alkyl dimethyl benzyl ammonium chloride is availablein an approximately 80% active ingredient solution as BTC-8358 fromStepan Co. (Northfield, Illinois); Bio-Quat-80-28RX from Bio Lab, andBarquat-MB80-10 is available from Lonza. The latter two have an alkyldistribution of approximately C₁₄ (50%), C₁₂ (40%) and C₁₆ (10%), anddiluents of ethyl alcohol (10%) and water (10%). In addition, a dialkyldimethylbenzyl ammonium saccharinate in 33% alcohol solution isavailable from Stepan Company as Onyxide 3300.

If the additional antimicrobial ingredient is a phenolic derivative, anysuitable phenol compound may be used. These include phenol, halogenatedphenols, phenylphenols particularly ortho-phenylphenol, xylenols,nitrophenols, cursols, thymol, nitrophenols, aminophenols, and manyothers well known in the art.

The compositions of this invention may also include one or moresurfactants in concentration ranging from 0.035 to about 10 weightpercent, preferably from 0.04 to 2 weight percent based on the totalweight of the composition (excluding the propellant required in aerosolformulations). The surfactants can be cationic, anionic, or nonionic.However, when the compositions contain a quaternary ammonium compound asan additional disinfecting agent, the surfactants present should belimited to nonionic surfactants.

Examples of suitable nonionic surfactants are as follows: ethoxylatedfatty alcohols containing from 11 to 15 carbon atoms in the alcohol andfrom 3 to 40 moles of ethylene oxide (Tergitol nonionics, Union CarbideCorporation), isomeric linear secondary alcohols with 11 to 15 carbonatoms and 9 moles of ethylene oxide (Tergitol 15-S-9), and linearprimary alcohols with 12 to 15 carbon atoms and 9 moles of ethyleneoxide (Tergitol 25-L-9); the block copolymers ofpolyoxyethylenepolyoxypropylene ("Tetronic series nonionic surfactants",BASF Wyandotte Corporation); ethylene glycol-reactedpolyoxyethylene-polyoxypropylene copolymers of the formula [HO(CH₂ C-H₂O)_(x) (CHCH₃ --CH₂ O)_(y) (CH₂ CH₂ O)_(z))₂ H], such as, for example,where x, y and z respectively are 13, 30 and 13 (Pluronic L-64; BASFWyandotte Corporation); alkyl phenol ethoxylates such asnonylphenoxypolyethoxyephenol ethoxylates ornonylphenoxypolyethoxyethanol with 9 to 10 moles of ethylene oxide(Triton N-101; Rohm & Haas Co.); alkanolamides for example, fatty acidalkanolamides having one or two hydroxyethyl or hydroxypropyl groupssuch as coconut and tallow fatty acid ethanolamide and diethanolamide,and oleic acid diethanolamide; and silicone glycol copolymers such asthose sold as Dow Corning 190, 193 or 1315.

The compositions of this invention should have a pH in the range of 8 to11. In order to attain a suitable pH, it is usually necessary to addalkalising agents which include well-known substances such as sodiumhydroxide, potassium hydroxide, ammonium hydroxide, mono-, di- andtri-ethanol amines, and other agents well known in the art.

The compositions of the invention may also comprise one or more optionalconstituents including, but not limited to: pH buffering agents,preservatives, fragrances, fragrance carriers and adjuvants whichincrease their miscibility in the aqueous compositions, colorants,hydrotropes, antifoaming agents, anti-oxidants and corrosion inhibitors,as well as others known to the art but not particularly elucidatedherein.

In a preferred form, the compositions of this invention are supplied inself-contained valve controlled aerosol units which provide a fine sprayor foam upon activation of the valve. The aerosol container unitconsists of a pressure-tight aerosol container having a valve controlopening and containing the composition of this invention and from about2 to about 10% of a propellant. Propellants are selected from the wellknown compatible propellants such as carbon dioxide, isobutane,n-butane, n-propane and mixtures thereof. The propellant used should notadversely react with any components of the composition.

In the methods according to this invention, the subject compositions aresprayed onto textile surfaces such as sofas, upholstered chairs,bedding, pillows, rugs, carpets, etc. known to be infested with dustmites. Although in describing all of these methods, emphasis is placedon dust mites and their allergens, it should be understood that thesemethods are equally effective against dust particles in general andagainst other allergens associated therewith, including pollen andanimal dander. The preferred mode of application is by means of aself-contained aerosol spraying device. Spraying should be carefullydone, ensuring that, for example, all sides of pillows are sprayed, thatthe spray reaches to comers and crevices, etc. The spraying step alonewill reduce the amount of allergens by preventing the escape of dustmite faecal particles into the ambient atmosphere.

A more effective method of dust mite control involves an initial step ofvacuuming up from textile surfaces as many as possible of the dust mitesand their associated faecal particles. It is important, when performingthis step, that the vacuuming be done under conditions whereby theparticles are not blown into the ambient air. A central vacuum system,where a holding bag is remote from the area being cleaned, will fulfillthis purpose. However, since this is not practical in most households,an acceptable alternative is to use a vacuum system which has a highperformance filter, such HEPA filters, or to employ a two-ply vacuumbag. Immediately after the vacuuming step, the compositions of thisinvention should be sprayed onto the textile surfaces according to themethod described above. It is particularly advantageous to apply thecompositions immediately after vacuuming since the vacuuming step willhave removed most of the dust particles, thereby permitting the filmformed by the composition to make closer contact with the fabricsurface. Additionally, if the composition contains an acaricidalingredient, such as benzyl benzoate, the composition will also kill offthe mites which have not been removed in the vacuuming step.

An even more effective method of dust mite control includes, as apreliminary first step, the application of a composition comprising anacaricidally effective ingredient such as, for example, benzyl benzoate.These compositions, which are most conveniently applied in aerosol form,should be sprayed onto the fabric surface, permitted to dry, and thenvacuumed up with a vacuuming system of the type described in theforegoing paragraph.

In this method, which is recommended for severe mite infestations, thedust mites are killed, and the dead mites and their faecal particles areremoved. This should be followed up immediately by spraying onto thesurface a composition according to this invention. If the compositionincludes an acaricidal ingredient, such as benzyl benzoate, in additionto the film forming polymer, any mites which survived the onslaught ofthe first two steps of the process, are likely to be killed.

The invention will be better understood by reference to the followingexamples, which are included for purposes of illustration only.

EXAMPLE 1

A liquid composition was prepared which had the following ingredients inthe percentage indicated:

    ______________________________________                                        Ingredient           wt. %                                                    ______________________________________                                        Anhydrous ethanol.sup.1                                                                            82.741                                                   Amphomer LV-71.sup.2 3.646                                                    Aminomethylpropanol (AMP) 95.sup.3                                                                 0.750                                                    Onyxide 3300 (33%).sup.4                                                                           0.334                                                    Corrosion inhibitors 0.500                                                    Fragrance            0.052                                                    DI Water             11.977                                                   ______________________________________                                         .sup.1 SDA 402; USI Chemical                                                  .sup.2 Amphoteric acrylic polymer; National Starch & Chemical Co.             .sup.3 Angus Chemical Company                                                 .sup.4 Quarternary antimicrobial surfactant; Stepan Company              

Into a clean dry mixing vessel containing the ethanol, Amphomer LV-71was slowly added under agitation until the polymer dissolved. AMP 95 wasthen added and mixed until uniform. The remaining ingredients were addedin the order indicated above. The pH was measured and shown to be in therange of 9.0 to 10.6.

An aerosol formulation was then prepared which contained 96% by weightof the above-described liquid composition and 4% of carbon dioxide. Thepressure range was 95 to 105 psi.

EXAMPLE 2

A liquid formulation was prepared which had the following constituentsin the percentages indicated.

    ______________________________________                                        Ingredient           wt. %                                                    ______________________________________                                        Anhydrous ethanol    82.741                                                   Benzyl Benzoate.sup.5                                                                              4.792                                                    Onyxide 3300 (33%)   0.334                                                    Amphomer LV-71       3.646                                                    Aminomethylpropanol (AMP) 95                                                                       0.750                                                    Corrosion inhibitors 0.500                                                    Fragrance            0.052                                                    DI Water             7.185                                                    ______________________________________                                         .sup.5 Kalama Chemical Co.                                               

The method of preparation was identical to that of Example 1 with theadditional ingredient, benzyl benzoate, being added concurrently withthe Onyxide 3300. A clear colorless solution was obtained having a pHrange of from 9.0% to 10.6%.

An aerosol formulation was then prepared which contained 96% by weightof the above-described liquid and 4% of carbon dioxide.

The formulations of Examples 1 and 2 were tested on fabric samples andthe results showed reduction in the numbers of dust mites and in theamount of dust particles.

EXAMPLES 3-7

Using the general methods of Examples 1 and 2, additional liquidcompositions were prepared having the following ingredients in thepercentage indicated. In preparing these compositions, the ammoniumhydroxide was the last ingredient added and was added in sufficientamount to provide a pH within the desired range.

    ______________________________________                                                   Weight %                                                           Ingredient   Ex. 3   Ex. 4   Ex. 5 Ex. 6 Ex. 7                                ______________________________________                                        Anhydrous ethanol                                                                          82.741  82.741  82.741                                                                              89.662                                                                              82.745                               Amphomer LV-71                                                                             5.208                       5.208                                Advantage Plus.sup.6 5.208                                                    PVP K-30.sup.7               5.208                                            Dermacryl 79.sup.8                 3.954                                      Benzyl Benzoate                    4.792                                      Aminomethyl propanol                                                                       0.911   0.911   0.911       0.911                                Ammonyx DMCD-40.sup.9                                                                      0.200   0.200   0.200 0.200 0.200                                Triethanolamine (99%)                                                                              0.200   0.200 0.200 0.200                                Onyxide 3300                       0.334                                      FC-138.sup.10        1.000   1.000                                            Forestall.sup.11                         0.061                                Ammonium Hydroxide                                                                         0.100   0.100   0.100 0.650 0.100                                (26 baume)                                                                    Silwet 7002.sup.12                 0.208                                      Dl Water     10.640  9.640   9.640       10.574                               ______________________________________                                         .sup.6 copolymer of vinyl acetate, butyl maleate and isobornyl acrylate i     ethanol                                                                       .sup.7 polyvinylpyrrolidone                                                   .sup.8 acrylate copolymer comprising octylacrylates, butylacrylates and       methacrylate                                                                  .sup.9 lauryldimethylamine oxide (40%)                                        .sup.10 fluorosurfactant: flurochemical salt in isopropanol and 2butoxy       ethano                                                                        .sup.11 Nsoya-N-ethylmorpholinium ethosulphate                                .sup.12 polyalkyleneoxide modified polydimethylsiloxane                  

Aerosol formulations were prepared from all of the foregoingcompositions which contained 96% by weight of said liquid compositionsand 4% of carbon dioxide.

While described in terms of the currently preferred embodiments, it isto be understood that the present disclosure is to be interpreted as byway of illustration, and not by way of limitation, and that variousmodifications and alterations apparent to one skilled in the art may bemade without departing from the scope and spirit of the invention.

We claim:
 1. A composition suitable for spraying onto a surface of afabric which, excluding any propellant which may be present, comprisesfrom 30% to 90% of a C₁ -C₄ alcohol, from 0% to 59% of water, aneffective amount of benzyl benzoate as an acaricidal agent, and from 1%to 20% of a polymer soluble in said alcohol which, upon evaporation ofthe alcohol and water, leaves a film on said surface.
 2. A compositionaccording to claim 1 in which the alcohol is ethanol.
 3. A compositionaccording to claim 2 which comprises from 1% to 7% of the polymer.
 4. Acomposition according to claim 3 which comprises from 70% to 85% ethanoland from 2% to 5% of the polymer.
 5. A composition according to claim 1in which the polymer is an acrylate polymer or copolymer.
 6. Acomposition according to claim 1 in which the benzyl benzoate is presentin an amount of from about 0.1% to about 10.0% by weight.
 7. Acomposition according to claim 1 which additionally comprises one ormore antimicrobial ingredients.
 8. A composition according to claim 7 inwhich an antimicrobial ingredient is a quaternary ammonium salt.
 9. Acomposition according to claim 1 which comprises from 0% to 15% water.10. A self-contained aerosol formulation which comprises from 90 to 98%of a composition according to claim 1 and from 2% to 10% of apropellent.
 11. An aerosol formulation according to claim 10 in whichthe composition additionally comprises one or more antimicrobialingredients.
 12. An aerosol formulation according to claim 11 in whichan antimicrobial ingredient is a quaternary ammonium salt.